Apparatus for continuous control of the degree of a reaction between two fluid reagents in which each of the reagents has a specific gravity different from the specific gravity of the reaction product



Nov. 16, 1965 M. BALLESTRA APPARATUS FOR CONTINUOUS CONTROL OF THE DEGREE OF A REACTION BETWEEN TWO FLUID REAGENTS IN WHICH EACH OF THE REAGENTS HAS A SPECIFIC GRAVITY DIFFERENT FROM THE SPECIFIC GRAVITY OF THE REACTION PRODUCT 2 Sheets-Sheet 1 Filed March 8, 1965 New. 16, 1965 M. BALLESTRA 3,217,729

APPARATUS FOR CONTINUOUS CONTROL OF THE DEGREE OF A REACTION BETWEEN TWO FLUID REAGENTS IN WHICH EACH OF THE REAGENTS HAS A SPECIFIC GRAVITY DIFFERENT FROM THE SPECIFIC GRAVITY OF THE REACTION PRODUCT Filed March 8, 1965 2 Sheets-Sheet 2- United States Patent 3,217,729 APPARATUS FOR CONTINUOUS CONTROL OF THE DEGREE OF A REACTION BETWEEN TWO FLUID REAGENTS IN WHICH EACH OF THE REAGENTS HAS A SPECIFIC GRAVITY DIFFER- ENT FROM THE SPECIFIC GRAVITY OF THE REACTION PRODUCT Mario Ballestra, Viale Bianca Maria 26, Milan, Italy Filed Mar. 8, 1965, Ser. No. 438,028 Claims priority, application Italy, Dec. 17, 1959, 622,387/ 59 3 Claims. (Cl. 137-91) This is a continuation in part of my application Serial No. 57,052, filed September 19, 1960 now abandoned.

The present invention relates to an apparatus for continuous control of the degree of a reaction between two fluid reagents in which each of the reagents has a specific gravity different from the specific gravity of the reaction product.

The irregular or anyhow discontinuous control of a reaction carries as a consequence that the possible correction in plus or minus of one of the reagents occurs always late with respect to the removal of the sample, which makes necessary a continuous and extended recycling of the product.

The apparatus according to the invention provides a substantially automatic control of the reaction product, allowing control in a quick way.

The apparatus for continuous control of the degree of a reaction between two fluid reagents, in which each of the reagents has specific gravity different from the specific gravity of the reaction product, comprises a container constantly full of the liquid product of the reaction. The container is constantly traversed by the reaction product and immersed in a liquid preferably constituted by one of the reagents, and is fixed at the end of a scale arm on which it is maintained in balance by a counterweight the moment of which, with respect to the scale fulcrum, is equal to the moment, with respect to the same fulcrum, of the buoyancy acting on the container when the latter is full of the reaction product.

Such an automatic control apparatus is characterized in that the displacements in plus or minus of the scale pointer, beyond a fixed tolerance interval, and corresponding to an incomplete degree of reaction, cause a positive or negative variation in the speed of the feeding pump of one of the reagents, an increase or decrease in delivery of the pump corresponding thereto. The duration of the variation in the pump delivery is pre-fixed by a timer acted upon by the scale pointer when the latter moves from the balance position beyond the fixed tolerance interval. When the interval of time during which the pump delivery increases positively or negatively is over, a second timer prevents the pump delivery from varying for a second pre-fixed interval of time, even though the scale pointer has not yet returned to the balance position. This second timer has for its object to take into consideration the apparatus inertia, that is the delay by which the scale ascertains the effects of the variation in the pump delivery.

An embodiment of the apparatus suitable to realize the method according to the invention is shown, by way of example only, in the accompanying drawings. FIG. 1 is a general diagram of the apparatus; FIG. 2 is a diagram in enlarged scale, of a thermostatic scale; FIG. 3 an electric schematic suitable to realize, through two equal timers, though calibrated for different interval of times, the control of the variation in delivery of the feeding pump of one of the reagents.

With reference to the figures: numeral 1 is a continuous or discontinuous mixer, within which the reaction 3,217,729 Patented Nov. 16, 1965 to be controlled in a continuous manner occurs; 2 is a stirring device arranged inside mixer 1; 3 is a motor driving the stirring device 2; 4 is the inlet pipe of one of the reagents and 5 the inlet pipe of the other reagent. The proportioning of which is effected by a pump 6 provided with a motor 8 and a speed variator 7; 9 is a flywheel of said variator; 12 and 13 are two switches acting on the speed variator 7 in opposite direction according to the direction of displacement from the balance position of the scale pointer; 10 is a timer fixing the duration of the action of the speed variator; when said interval of time is over, a timer 11 prevents, for a second pre-fixed interval of time, the speed variator 7 from acting on the delivery of pump 6, even though the scale pointer still keeps out of the balance position. That allows to take into consideration the inertia of the apparatus that is the delay by which the scale ascertains the correction of delivery effected on the pump; 14 is a casing enclosing the scale, said casing being filled with a liquid kept at constant temperature by means of a heat source and a regulation thermostat; 15 is a tape device registering the behaviour of the density variations; 16 is a recycling pump for the reaction product; 17 is a sampling pump, which is passed through a heat exchanger 18 to bring it to a constant temperature and then is forwarded to the scale; 19 is a pipe for recycling the weighed sample; 20 is a container, with exactly defined volume, entered by the product which comes from a pipe 23, after passing through a coil 22 arranged between the inlet of casing 23 and container 20, and goes out through a pipe 24, a coil 25 and a casing 26; 27 is one of the scale arms to which the container 20 is connected; 28 is the fulcrum of the scale and 29 the other scale arm on which a movable counterweight 30 is arranged; 31 is a device showing the scale oscillations.

The above described apparatus works as follows: two reagents reach mixer 1 from pipes 4 and 5 in their stoichiometric proportions to obtain the reaction product, and are mixed by means of the stirring device 2 and recycled by means of pump 16. A sample of the product is taken in a continuous manner by means of pump 17 positive or negative increase in the pump delivery; timer. 11 controls that between one variation and the other.

in the pump delivery there is at least a pre-fixed interval of time, any may be the position of the scale pointer.

The sample is taken continuously and therefore the regulation of the delivery of one of the reagents is continuous.

To better clear up the method and working of the scale the following example of sulphonation of dodecylbenzol is reported herebelow.

The density of the dodecylbenzol is 0.890; the density of sulphonic acid is 1.050. The capacity of the container is of two liters and its weight when empty is of 200 grs. The weight of the container when filled with sulphonic acid is in the :air of grs. 2.300, its volume is of 2.011 liters. By filling the casing containing the scale with glycerine with 55%. of glycerol, having a density of about 1.44 thermostated .at 15 0., there would occur the balance of the container in case the latter contains only sulphonic acid, as a matter of fact: container volume specific gravity of glycerine with 55% of glycerol-:weight of container full of sulphonic acid.

Should the container contain e.g. 99% of sulphonic acid and 1% of unsulphonated dodecylbenzol, it would weigh in the air 2,296.8 grs., with a difference of 3.2 grs. Therefore, each diflference in minus of 3.2 grs. (the double of the difference of the specific gravities of the product and reagent, since the container has the capacity of 2 liters) shows the presence of the 1% unsulphonated; a difference in plus shows on the contrary an excessof sulphuric acid. The scale with its continuous oscillation will be able to correct in a continuous manner the defeet or excess of one of the reagents, so as to obtain a pure product.

In a different preferred case, the reference liquid hold in casing 14 and in which the container is immensed, is constituted by a liquid which specific gravity is comprised between the specific gravity of the liquid product of the reaction and the specific gravity of one of the liquid reagents of said reaction. Particularly, it may be constituted by one of the liquid reagents itself. In such cases the counterweight 30 will be arranged in such a way that when the container is full of the pure reaction product, the buoyancy on the container is balanced by said counterweight 30.

With particular reference to FIG. 3, l2 and 13 are respectively the closed contacts of the scale pointer when the latter moves from the balance position to one direction or the other respectively, beyond a pre-fixed tolerance interval; 32 is a source of low voltage electric power feeding the circuit control circuits shown by a thin line; 33 is on the contrary a source of higher voltage electric power feeding the motor of flywheel 9 to one direction or the other so as to vary in plus or minus the delivery of pump 6 by means of variator 7; 34 and 35 respectively are two coils energized by the closure of contacts 12, 13 respectively; 36, 38, 40 and 37, 39, 41 respectively are contacts which are closed when coil 34 or coil 35 respectively are energized; contacts 42 and 43 respectively are on the contrary open when the corresponding coils are energized. Timer is formed by coils 44 and 45, by the pair of contacts 46 and 48 which are closed when coil 44 is energized and by the pair of contacts 47 and 49 the first of which is opened and the latter closed when it is passed a prefixed interval of time At from the moment when coil 45 has been energized. The mentioned contacts 47 and 49 remain in their cited position as long as coil 44 keeps being energized and then they return to their rest position shown in figure together with contacts 46 and 48. The working of timer 10 is known per se and is common for all timers of the same type, particularly it is common for timer 11. The latter comprises: two coils 50 and 51; a contact 52 which is open when coil 50 is energized; contacts 53 and 55 which are opened when it is passed a pre-fixed interval of time At from the moment when coil 51 has been energized and which remain open as long as coil 50 of the same timer keeps energized. Coil 56, when it is energized, opens contact 58 and at the same time closes contacts 60, 62, 64, 66. The closing of said last three cont-acts causes the rotation to a given direction of the motor of the flywheel 9. The energization of coil 56 is caused by the closing of contact 12. The duration of the energization phase of coil 56 is pre-fixed by timer 10, while the interval of time between one period of energization and the successive one of coil 56 is controlled by timer 11.

In the same way, coil 57, when it is energized, causes the opening of contact 67 and the contemporaneous closure of contacts 59, 61, 63, 65; the closure of said last three contacts causes the rotation of the motor of flywheel 9 to the opposite direction with respect to that caused by the energization of coil 56 in the aforecited case.

The energization of coil 57 is caused by the closure of contact 13, while the duration of the energization phase of said coil and the length of the interval of time between one energization period and the successive one are controlled by timer 10 and timer 11 respectively.

Contacts 68 are to be closed by hand in order that the apparatus may work automatically; lamps 69 and 70 are turned on by the closure of contacts 13 and 12 respectively and mean that the regulation apparatus is working to correct to one direction or the other the reaction degree of the reaction product.

When the scale pointer is in its balance position and the apparatus in its position of automatic control, contacts 68 are closed, while all the other contacts are in the position shown in FIG. 3.

When the displacement of the scale pointer from its position closes e.g. contacts 12, the working is the following:

After an interval of time equal to At timer 10 by means of coil 45 effects the opening of contact 47 and the closure of contact 49. With respect to the previously described position, the various elements of the electric installation of regulation are subject to the following variations of operation:

(a) coils 50 and 51 are energized;

(b) contact 52 is open;

(0) coil 56 is not energized any longer; (d) contact 58 is closed;

(e) contacts 60, 62 64, 66 are open; (f) the motor of flywheel 9 is arrested.

After an interval of time equal to At from the previously considered moment, timer 11 effects, through coil 51, the opening of contacts 53, 55. With respect to the above described position, the various elements of the electric installation of regulation are subject to the following variations of operation:

(a) coil 45 is de-energized and the contacts 47 and 49, in consequence thereof, return to their rest position, that is the former is closed and the latter open;

(b) contact 49 being open, coil 50 is de-energized and thus contacts 52, 53, 55 return to their rest position, that is to the closed position.

At this time if the scale pointer has returned to its balance position, the apparatus remains in the position shown in FIG. 3 with the only exception that switches 68 are closed in the position of automatic operation. If the scale pointer has not yet returned to its balance position, notwithstanding the proportioning correction effected by pump 6, contact 12 is still in the closed position and the operation cycle starts again. pointer has moved beyond the balance position because the proportioning correction has been excessive, contact 13 will be closed and the operating cycle of correction will be repeated again as described, with the only exception that coils 37 and 57 instead of coils 34 and 56 will be interested and that the motor of flywheel 9 will turn in a direction opposite to the previous one; the two timers will operate as aforedescribed.

Although for describing reasons the present inventionv has been shown on the ground of what above stated, many modifications and changes may be made in embodying; the invention, either for what refers to the arrangement. and embodiment of the apparatus, or for what refers to the shape, volume and arrangement of the weighing con-- tainer, all these modifications and changes however,

If on the contrary the scale ing based on the main ideas of the invention as resumed in the following claims.

What I claim is:

1. An apparatus for continuous control of the degree of a reaction between two fluid reagents in which each of the reagents has a specific gravity difierent from the specific gravity of the reaction product, comprising a reaction vessel, a container of known volume, means for continuously passing liquid product from the reaction vessel through said container to constantly maintain said container filled with reaction liquid product, said container being completely immersed in a liquid of known specific gravity constituted preferably by one of the reagents; said container being further arranged at the end of a scale arm on which it is maintained in balance by a counterweight the moment of which, with respect to the scale fulcrum, is equal to the moment, with respect to the same fulcrum, of the buoyancy acting on the container when the latter is full of the pure product of the reaction; a pump arranged to feed one of the reagents to the reaction vessel, means responsive to the displacements of the scale pointer in plus and minus beyond a pre-fixed tolerance interval for causing a positive or negative variation in the speed of the feeding pump of said one of the reagents constructed and arranged so that an increase or decrease in the delivery of the said pump corresponds to said plus and minus displacements; said means including a suitable system of timers constructed and arranged for pre-fixing both the duration of variation in the pump de- 6 livery and the duration of a successive interval of time during which the pump delivery is maintained on the normal value independently of the position of the scale pointer, in order to take into consideration the apparatus inertia, that is the delay by which the scale ascertains the efiects of the variation in the pump delivery.

2. An apparatus according to claim 1, wherein the system of timers comprises: first timer means responsive to movement of the scale pointer beyond a pre-fixed tolerance interval for pre-fixing the duration of variation in pump delivery; second timer means in series with the first timer means and responsive to the first timer means and including means constructed and arranged to prevent further variations of pump delivery for a pre-fixed interval of time regardless of the position of the scale pointer.

3. An apparatus according to claim 2, in which said second timer means comprises means for causing the last pre-fixed interval of time to correspond to substantially a period of time between delivery of a given quantity of reagent from said pump and delivery of a reaction product obtained from said quantity of reagent to said container.

References Cited by the Examiner UNITED STATES PATENTS 3,004,544 10/1961 Guptill 73434 X ISADOR WEIL, Primary Examiner. 

1. AN APPARATUS FOR CONTINUOUS CONTROL OF THE DEGREE OF A REACTION BETWEEN TWO FLUID REAGENTS IN WHICH EACH OF THE REAGENTS HAS A SPECIFIC GRAVITY DIFFERENT FROM THE SPECIFIC GRAVITY OF THE REACTION PRODUCT, COMPRISING A REACTION VESSEL, A CONTAINER OF KNOWN VOLUME, MEANS FOR CONTINUOUSLY PASSING LIQUID PRODUCT FROM THE REACTION VESSEL THROUGH SAID CONTAINER TO CONSTANTLY MAINTAIN SAID CONTAINER FILLED WITH REACTION LIQUID PRODUCT, SAID CONTAINER BEING COMPLETELY IMMERSED IN A LIQUID OF KNOWN SPECIFIC GRAVITY CONSTITUTED PREFERABLY BY ONE OF THE REAGENTS; SAID CONTAINER BEING FURTHER ARRANGED AT THE END OF A SCALE ARM ON WHICH IT IS MAINTAINED IN BALANCE BY A COUNTERWEIGHT THE MOMENT OF WHICH, WITH RESPECT TO THE SCALE FULCRUM, IS EQUAL TO THE MOMENT, WITH RESPECT TO THE SAME FULCRUM, OF THE BUOYANCY ACTING ON THE CONTAINER WHEN THE LATTER IS FULL OF THE PURE PRODUCT OF THE REACTION; A PUMP ARRANGED TO FEED ONE OF THE REAGENTS TO THE REACTION VESSEL, MEANS RESPONSIVE TO THE DISPLACEMENTS OF THE SCALE POINTER IN PLUS AND MINUS BEYOND A PRE-FIXED TOLERANCE INTERVAL FOR CAUSING A POSITIVE OR NEGATIVE VATIATION IN THE SPEED OF THE FEEDING PUMP OF SAID ONE OF THE REAGENTS CONSTRUCTED AND ARRANGED SO THAT AN INCREASE OR DECREASE IN THE DELIVERY OF THE SAID PUMP CORRESPONDS TO SAID PLUS AND MINUS DISPLACEMENTS; SAID MEANS INCLUDING A SUITABLE SYSTEM OF TIMERS CONSTRUCTED AND ARRANGED FOR PRE-FIXING BOTH THE DURATION OF VARIATION IN THE PUMP DELIVERY AND THE DURATION OF A SUCCESSIVE INTERVAL OF TIME DURING WHICH THE PUMP DELIVERY IS MAINTAINED ON THE NORMAL VALUE INDEPENDENTLY OF THE POSITION OF THE SCALE POINTER, IN ORDER TO TAKE INTO CONSIDERATION THE APPARATUS INERTIA, THAT IS THE DELAY BY WHICH THE SCALE ASCERTAINS THE EFFECTS OF THE VARIATION IN THE PUMP DELIVERY. 